Accurate spatio-temporal modeling of regionalized data is indispensable to environmental problems such as water and air pollutions. This modeling can contribute to specify influence factors and clarify mechanism of the worsening of environments. Geostatistics is adopted to construct a distribution model by considering spatio-temporal correlation structures included in the regionalized data. Data of sea surface temperature (SST) and concentration data of four nutritive salts, NO2-N, NO3-N, NH4-N, and PO4-P, in the Ariake Sea, southwest Japan, were chosen for a case study of geostatistics to environmental problem in closed seas. These data were sampled monthly between 1975 and 2000 at the 43 stations over the Ariake Sea. The first examination is proper modeling of spatio-temporal semivariogram of univariate on which estimation accuracy of kriging strongly depends: piecewise polynomial model using smoothed cubic spline was demonstrated to be superior to product-sum model, because it could follow complicated changes in experimental semivariogram. The difference in spatio-temporal correlations between the SST and nutritive salts was clarified by the semivariogram models. Estimation accuracy of ordinary kriging was checked through the cross-validation for all the sample data, which proved high estimation accuracy for the SST and acceptable accuracy for the nutritive salts with considering only the space direction. Temporal changes of the SST and four nutritive salt concentrations in summer and winter were depicted with clarifying the characteristics of fluctuation patterns. One possible influence factor for sea environmental change is decline of nitrification activity in the northern part of Ariake Sea in winter, because the rations of NO2-N/NH4-N and NO3-N/NH4-N have seemed to decrease from 1997.

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The 2003 off Tokachi earthquake with Mw 8.0, thought to be a megathrust earthquake, occurred on 26 September in 2003. The R/V KAIREI KR03-14 (JAMSTEC) surveyed off Tokachi in December of 2003, focusing on the multi-channel seismic (MCS) and multibeam bathymetry sueveys to find any traces after the shock. We have already operated geophysical line/box surveys including bathymetry, gravity, and total and three-component geomagnetics, MCS survey and submersible investigations during Legs KR99-02 in July of 1999, KR00-04 in June of 2000 and YK02-02 in May of 2002, which are all including and the public domain in the Geophysical Database on the web site.

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Geometric parameters/features of folds play a major role in classifying the folds in several ways as well as in making any systematic and comparative study of the various fold types in a structurally deformed terrain. The following parameters of fold geometry enable a simple classification of single-layer, symmetric, natural folds : thickness ratio (R), i.e. the ratio existing between the hinge thickness and the limb thickness ; axial angle (α) which is the angle for a given (outer or inner) trace or arc of a fold as subtended at the apex (hinge), and outer axial angle (αo) and inner axial angle (αi) which are the acute angles subtended by the outer and inner arcs respectively at the apex (hinge). Folds which are assumed to have initiated by buckling and have undergone thickening at the hinges are thus considered here as T (thickened) folds. Folds showing uniform layer thickness and with both the outer (αo ) and inner (αi ) axial angles of equal value constitute P (parallel) folds, while those in which the hinge thickness is less than the limb thickness - and therefore the inner axial angle ((αi) is smaller than the outer one (αo) - constitute S (supratenuous) folds. Folds which practically do not show any geometric relation between the above parameters constitute F (flow) folds that may form from any of the above (T, P or S) fold types at later/advanced stages of deformation. Each of these four types of folds thus show some definite values/conditions of the above-mentioned geometric parameters : for P-folds, T = 1, αo = αi ; for T-folds, T > 1, αo < αi ; for S-folds, T < 1, αo > αi , while for F-folds, no definite geometric relations amongst the above parameters exist.

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In highway projects, balancing cut-fill is an important way to minimize economic payout. As the result, cut-fill calculation becomes a necessary work to the highway designer. Traditionally, cut-fill planning is not only a slow, laborious work, but also one of the problems in the feasibility analysis. With the large-scale products of Digital Elevation Model (DEM) shared up and put to use, automatic analysis for cut-fill projects is provided with reliable authenticity. This paper tries to develop a cut-fill algorithm on the basis of ARC/INFO GRID on the condition of the unknown hypsography resulted from the cut-fill diffusion model, provided with pre-cut-fill DEM and road coverage, engineering side-slope, road height and width. The aim of this paper is to propose the algorithm to calculate excavation- amount, fill-amount, and simulate the post-cut-filled DEM when the supposed cut-fill is done. This algorithm is feasible based on current GIS software, can save a lot time for the highway designers and offer a considerable cut-fill designing.

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